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/* GchemIB Bright Study Edition — clean, vivid, print-ready */
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/* Detailed topic lessons and written-response practice */
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/* Scope and sequence roadmap */
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@media(max-width:900px){.sequence-terms{grid-template-columns:1fr}}
@media print{.sequence-term{break-inside:avoid}.sequence-note{background:#fff!important}}

/* Visual chemistry field-guide notes */
.topic-hero{display:grid;grid-template-columns:minmax(0,1.35fr) minmax(180px,.65fr);gap:22px;align-items:center;padding:26px 28px;margin:12px 0 18px;border:1px solid #dce6fb;border-radius:20px;background:radial-gradient(circle at 82% 18%,rgba(19,168,158,.14),transparent 32%),linear-gradient(135deg,#f5f7ff 0%,#effaf8 100%);overflow:hidden}.topic-hero-copy h2{font-size:clamp(25px,3vw,36px);line-height:1.15;letter-spacing:-.7px;margin:10px 0 12px;color:#202e4a}.topic-hero-label{font-size:10px;letter-spacing:1.5px;font-weight:850;color:#5369c8}.topic-hero .note-intro{max-width:650px;font-size:15px;line-height:1.75;color:#52617b;margin:0}.topic-hero-pills{display:flex;flex-wrap:wrap;gap:7px;margin-top:17px}.topic-hero-pills span{font-size:11px;font-weight:750;padding:6px 10px;border:1px solid #dce4f8;background:rgba(255,255,255,.75);border-radius:999px;color:#4659a7}.topic-hero-art{display:flex;flex-direction:column;align-items:center;justify-content:center;min-height:145px;padding:12px;border-radius:15px;background:rgba(255,255,255,.68);border:1px solid rgba(211,223,244,.9);color:#6177cb}.topic-art{display:block;width:100%;max-width:245px;height:auto;overflow:visible}.topic-hero-art>span{font-size:11px;font-weight:750;letter-spacing:.3px;color:#64718b;margin-top:3px}.topic-video-card{display:flex;align-items:center;gap:15px;padding:16px 18px;margin:18px 0 23px;border:1px solid #e0e6f1;border-radius:15px;background:#fff;box-shadow:0 6px 20px rgba(35,52,83,.045)}.video-icon{display:grid;place-items:center;flex:0 0 42px;width:42px;height:42px;border-radius:13px;background:#fff0f0;color:#e04444;font-size:17px}.topic-video-copy{flex:1;min-width:0}.topic-video-copy strong{font-size:14px;color:#283651}.topic-video-copy p{font-size:12px;line-height:1.55;color:#68758d;margin:4px 0 0}.topic-video-link{flex-shrink:0;text-decoration:none;white-space:nowrap}.note-learning{padding:19px 21px;border-radius:15px;background:#f7f8ff;border:1px solid #e5e8fb;margin:18px 0 22px}.note-learning h3{display:flex;align-items:center;gap:9px;margin:0 0 12px}.learning-spark{display:inline-grid;place-items:center;width:25px;height:25px;border-radius:8px;background:#e6eaff;color:#4f62ca}.note-learning ul{display:grid;grid-template-columns:1fr 1fr;gap:10px 22px;margin:0;padding-left:20px}.note-learning li{font-size:13px;line-height:1.6;padding-left:2px;color:#4f5d75}.visual-note-section{position:relative;margin:15px 0;padding:20px 22px;border:1px solid #e4e9f3;border-radius:16px;background:#fff;box-shadow:0 5px 18px rgba(33,49,78,.035);overflow:hidden}.visual-note-section:before{content:"";position:absolute;left:0;top:0;bottom:0;width:4px;background:linear-gradient(180deg,#6178e8,#26b7a5)}.note-section-top{display:flex;align-items:center;gap:10px;margin-bottom:10px}.visual-note-section .note-section-number{display:inline-grid;place-items:center;width:32px;height:32px;border-radius:10px;background:#edf0ff;color:#4e61c9;font-weight:850;font-size:12px}.note-section-label{font-size:9px;letter-spacing:1.2px;font-weight:850;color:#8a94a8}.visual-note-section h3{font-size:18px;line-height:1.35;margin:0 0 9px;color:#273651}.visual-note-section p{font-size:14px;line-height:1.8;color:#53617a;margin:0}.section-takeaway{display:flex;align-items:center;gap:10px;margin-top:14px;padding-top:11px;border-top:1px dashed #e1e7f0}.section-takeaway span{font-size:9px;letter-spacing:.9px;font-weight:850;color:#14998e;white-space:nowrap}.section-takeaway strong{font-size:11px;color:#63708a;font-weight:650}.note-callout,.example-box{border-radius:15px;padding:19px 21px;margin:17px 0}.note-callout{border:1px solid #f1dfb3;background:linear-gradient(135deg,#fff9e9,#fffdf7)}.example-box{border:1px solid #cfece6;background:linear-gradient(135deg,#effbf8,#f9fffd)}.note-callout>strong,.example-box>strong{display:block;font-size:10px;letter-spacing:1.1px;margin-bottom:7px}.note-callout>strong{color:#a36b12}.example-box>strong{color:#148d80}.note-callout p,.example-box p{font-size:14px;line-height:1.75;margin:0;color:#495873}
@media(max-width:700px){.topic-hero{grid-template-columns:1fr;padding:21px}.topic-hero-art{min-height:110px}.topic-hero-art .topic-art{max-width:210px}.topic-video-card{align-items:flex-start;flex-wrap:wrap}.topic-video-copy{flex-basis:calc(100% - 60px)}.topic-video-link{margin-left:57px}.note-learning ul{grid-template-columns:1fr}.visual-note-section{padding:17px 17px}.section-takeaway{align-items:flex-start;flex-direction:column;gap:4px}}
@media print{.topic-video-card,.note-actions,.screen-only{display:none!important}.topic-hero,.visual-note-section,.note-learning,.note-callout,.example-box{break-inside:avoid;box-shadow:none}.topic-hero{background:#f5f7ff!important}}

/* GchemIB Aurora palette + interactive learning cards */
:root{--bg:#f3f6fb;--panel:#ffffff;--panel2:#f8faff;--line:#dce5f2;--text:#17243b;--muted:#65748d;--teal:#0d9488;--blue:#5267d8;--purple:#8b5cf6;--amber:#e6a23c;--radius:18px;--shadow:0 14px 36px rgba(34,53,91,.09)}
body{background:radial-gradient(ellipse at 8% 0%,#e3f7f4 0,transparent 32%),radial-gradient(ellipse at 95% 8%,#eee9ff 0,transparent 29%),var(--bg);color:var(--text)}
.sidebar{background:#18243c;border-right-color:#263653}.brand-copy strong{color:#fff}.brand-copy small{color:#a9b8d2}.sidebar-label,.section-kicker{color:#94a6c4}.nav-link{color:#c1cce0}.nav-link:hover{background:#263654;color:#fff}.nav-link.active{background:linear-gradient(100deg,#234d62,#303b68);border-color:#42677c;color:#fff}.nav-count{background:#2a3a59;color:#d4e4f4}.mini-card{background:linear-gradient(145deg,#243e55,#282e50);border-color:#40526f}.topic-hero{background:linear-gradient(125deg,#e5f8f5,#f0efff 58%,#fff5e6)!important;border-color:#d8e6f3!important}.topic-hero h2,.topic-hero-copy{color:#1c2a45}.topic-hero-label{color:#0f827c}.topic-hero-pills span{background:#fff;color:#344461;border:1px solid #dce5f2}.topic-video-card,.note-learning,.visual-note-section,.topic-test-question,.formula-card,.panel,.stat-card{background:rgba(255,255,255,.94);border-color:#dce5f2;box-shadow:0 8px 24px rgba(34,53,91,.045)}.topic-video-copy strong,.visual-note-section h3{color:#202e49}.topic-video-copy p,.visual-note-section p,.note-learning li{color:#5b6982}.note-learning{background:linear-gradient(135deg,#f0f5ff,#f0fbf8)}.learning-spark{background:#dfe8ff;color:#4b5ed0}.visual-note-section:before{background:linear-gradient(180deg,#6578e8,#17aa9a)}.visual-note-section .note-section-number{background:#e7edff;color:#4f61c8}.note-callout{background:linear-gradient(135deg,#fff7e7,#fffdf8);border-color:#f1dfb3}.example-box{background:linear-gradient(135deg,#e8fbf6,#f8fffd);border-color:#c8eee4}.btn-primary{background:linear-gradient(120deg,#0f9488,#5267d8);border-color:transparent;color:#fff}.btn-primary:hover{filter:brightness(1.04)}
.interactive-section{padding:0}.interactive-section summary{list-style:none;display:flex;align-items:center;gap:12px;padding:19px 21px;cursor:pointer}.interactive-section summary::-webkit-details-marker{display:none}.section-summary-copy{display:grid;gap:4px;flex:1}.section-summary-copy strong{font-size:17px;line-height:1.35;color:#202e49}.section-toggle{display:grid;place-items:center;width:29px;height:29px;border-radius:9px;background:#e8edff;color:#4f61c8;font-size:20px;flex-shrink:0}.interactive-section[open] .section-toggle{transform:rotate(45deg);background:#ddf7f0;color:#0b877e}.section-content{padding:0 22px 20px 65px}.section-content p{margin:0}.interactive-section summary:focus-visible{outline:2px solid var(--teal);outline-offset:-4px;border-radius:14px}
@media(max-width:700px){.interactive-section summary{padding:16px}.section-content{padding:0 17px 18px 17px}.section-summary-copy strong{font-size:15px}}

/* Break lesson explanations into readable, numbered concept bites */
.concept-bites{display:grid;gap:9px;list-style:none;padding:0;margin:0}.concept-bites li{display:grid;grid-template-columns:28px minmax(0,1fr);align-items:start;gap:10px;padding:11px 13px;border:1px solid #e5ebf5;border-radius:12px;background:linear-gradient(100deg,#f8faff,#fff);color:#4e5d76;font-size:13px;line-height:1.7}.bite-dot{display:grid;place-items:center;width:25px;height:25px;border-radius:8px;background:#e4f6f2;color:#11877f;font-size:10px;font-weight:850}.section-content>p{margin:0}.topic-hero .note-intro{max-width:68ch}
@media(max-width:700px){.concept-bites li{font-size:12px;padding:10px;gap:8px}}

/* ─────────────────────────────────────────────────────────────
   GchemIB design refresh — balanced editorial study workspace
   ───────────────────────────────────────────────────────────── */
:root{--bg:#f5f6f8;--panel:#fff;--panel2:#f8fafc;--line:#e3e7ee;--text:#20283a;--muted:#697386;--teal:#167c75;--blue:#4866bd;--purple:#7861b0;--amber:#c58a35;--radius:16px;--shadow:0 8px 26px rgba(31,43,66,.055)}
html{scroll-behavior:smooth}body{background:#f5f6f8;color:#20283a;font-family:"DM Sans",Inter,system-ui,sans-serif;font-size:14px;line-height:1.6}button,input,select,textarea{font:inherit}button,a,input,select,textarea{transition:background-color .18s ease,border-color .18s ease,box-shadow .18s ease,transform .18s ease}
.app-shell{min-height:100vh}.sidebar{width:252px;background:#202a40;border:0;padding:27px 17px 20px;box-shadow:5px 0 24px rgba(29,40,62,.04)}.brand{padding:0 9px 30px}.brand-mark{border-radius:12px;background:#d7eee7;color:#244a49;box-shadow:none}.brand-copy strong{font-size:19px;color:#fff;letter-spacing:-.5px}.brand-copy small{color:#aebbd0;font-size:8px;letter-spacing:1.25px}.sidebar-label{color:#9aa8bf;font-size:9px;letter-spacing:1.5px;padding:0 12px 12px}.side-nav{gap:4px}.nav-link{padding:11px 12px;border-radius:10px;color:#c0c9d8;font-size:12px;font-weight:600}.nav-link:hover{background:#2b3852;color:#fff}.nav-link.active{background:#e1f1ed;border:1px solid #e1f1ed;color:#205d57}.nav-link.active .nav-icon{color:#247b72}.nav-icon{font-size:15px;color:#b2bfd1}.nav-count{background:#d0e8e1;color:#28685f}.mini-card{background:#293750;border:1px solid #3c4b65;border-radius:13px;padding:16px}.mini-card-icon{color:#b8e3d8}.mini-card strong{color:#fff}.mini-card p{color:#b9c5d7}.text-button{color:#c9eee5}.sidebar-foot{color:#aebbd0}
.main-area{margin-left:252px;min-width:0}.topbar{height:70px;padding:0 clamp(20px,3.3vw,48px);background:rgba(255,255,255,.9);border-bottom:1px solid #e6e9ef;backdrop-filter:blur(14px)}.breadcrumbs{font-size:12px;color:#858ea0}.breadcrumbs strong{color:#263148}.global-search{background:#f5f7fa;border:1px solid #e5e9f0;border-radius:10px}.global-search:focus-within,.search-field:focus-within{border-color:#94c9bd;box-shadow:0 0 0 3px #dff1ec}.global-search input{color:#29344b}.icon-button{background:#fff;border:1px solid #e3e7ee;color:#526076;border-radius:10px}.avatar{background:#e3f1ed;color:#2c6961}
.content-wrap{max-width:1480px;padding:30px clamp(20px,3.3vw,48px) 28px;margin:0 auto}.page{animation:pageIn .28s ease both}@keyframes pageIn{from{opacity:.65;transform:translateY(4px)}to{opacity:1;transform:translateY(0)}}
.hero{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(300px,.95fr);align-items:center;gap:clamp(22px,4vw,58px);padding:clamp(28px,4vw,52px);min-height:360px;border:1px solid #e2e7ee;border-radius:22px;background:linear-gradient(112deg,#fff 0%,#fff 53%,#f0f6f4 100%);box-shadow:0 10px 35px rgba(34,50,76,.045);overflow:hidden}.hero h1{font-size:clamp(34px,4vw,54px);line-height:1.08;letter-spacing:-2.2px;color:#202a40;margin:18px 0 15px}.hero h1 span{color:#267c72}.hero-copy>p{max-width:450px;color:#6a7486;font-size:14px;line-height:1.8}.eyebrow{color:#66768b;font-size:9px;letter-spacing:1.55px}.eyebrow-dot{background:#3a9c8b;box-shadow:0 0 0 4px #e3f4ee}.hero-actions{gap:10px;margin-top:23px}.btn{min-height:40px;border-radius:10px;padding:10px 15px;font-size:12px;font-weight:700;box-shadow:none}.btn-primary{background:#277e73;border:1px solid #277e73;color:#fff}.btn-primary:hover{background:#206c63;transform:translateY(-1px);box-shadow:0 6px 14px #277e7322}.btn-secondary{background:#fff;border:1px solid #dfe5ed;color:#3c4960}.btn-secondary:hover,.btn-ghost:hover{background:#f0f5f4;border-color:#cbded8}.btn-ghost{background:transparent;border:1px solid #e1e6ed;color:#48566d}.hero-proof{color:#758096;font-size:11px}.proof-avatars i{background:#e0f0eb;border-color:#fff;color:#276c63}.hero-visual{min-height:280px;border:1px solid #e1ebe7;border-radius:18px;background:radial-gradient(circle at 48% 45%,#e1f3ee 0,transparent 45%),linear-gradient(145deg,#f8fbfa,#edf3f4);overflow:hidden}.hero-visual .orb{opacity:.65}.molecule{max-width:100%;filter:saturate(.75)}.visual-caption{background:#fff;border:1px solid #e2e8ec;border-radius:12px;box-shadow:0 5px 18px #20344a0c;color:#28344b}.visual-caption small{color:#778194}.floating-chip{background:#fff;border:1px solid #e3e8ed;box-shadow:0 5px 18px #24374c0c;color:#44536a;border-radius:9px;font-size:10px}
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.page-intro{display:flex;align-items:center;justify-content:space-between;gap:22px;margin:3px 0 25px}.page-intro h1{font-size:clamp(28px,3vw,36px);line-height:1.2;letter-spacing:-1.2px;color:#202a40;margin:7px 0 9px}.page-intro p{color:#6e798d;font-size:12px;line-height:1.8;max-width:690px;margin:0}.intro-stat{min-width:110px;padding:15px 19px;border:1px solid #e2e8ed;border-radius:14px;background:#fff;text-align:center}.intro-stat strong{font-size:27px;line-height:1.2;color:#287d70;letter-spacing:-1px}.intro-stat span{display:block;color:#7b8698;font-size:10px;margin-top:4px}
.toolbar{display:flex;gap:11px;margin-bottom:18px}.search-field{min-height:43px;border:1px solid #e1e6ee;border-radius:11px;background:#fff}.search-field input,.toolbar select{color:#354158}.toolbar select{border:1px solid #e1e6ee;border-radius:11px;background:#fff;padding:0 13px;min-height:43px}
.notes-layout{display:grid;grid-template-columns:minmax(220px,270px) minmax(0,1fr);gap:20px;align-items:start}.topic-list{position:sticky;top:88px;max-height:calc(100vh - 112px);overflow:auto;padding:8px;border:1px solid #e3e7ee;border-radius:15px;background:#fff;box-shadow:0 5px 20px rgba(32,47,70,.025)}.topic-list button,.topic-item{border-radius:9px}.topic-list button:hover,.topic-item:hover{background:#f3f7f6}.topic-list button.active,.topic-item.active{background:#e4f2ee;color:#235f58;border-color:#cfe5de}.note-reader{min-width:0;border:1px solid #e3e7ee;border-radius:17px;background:#fff;padding:clamp(16px,2.1vw,28px);box-shadow:0 6px 24px rgba(32,47,70,.03)}.note-actions{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:17px}.topic-hero{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(190px,.75fr);gap:20px;align-items:center;padding:26px;border:1px solid #dceae5;border-radius:17px;background:linear-gradient(120deg,#f3faf7,#f3f5fc)!important;box-shadow:none}.topic-hero h2{font-size:clamp(23px,2.4vw,31px);line-height:1.2;letter-spacing:-.9px;color:#243148;margin:10px 0}.topic-hero .note-intro{font-size:12px;line-height:1.8;color:#68768b}.topic-hero-label{font-size:9px;letter-spacing:1.3px;color:#337f73}.topic-hero-pills{display:flex;flex-wrap:wrap;gap:7px;margin-top:15px}.topic-hero-pills span{font-size:9px;padding:5px 9px;border:1px solid #e0e9e6;border-radius:99px;background:#fff;color:#526579}.topic-hero-art{display:grid;justify-items:center;align-content:center;min-width:0;padding:12px}.topic-hero-art .topic-art{width:min(100%,220px);max-height:170px}.topic-hero-art>span{font-size:9px;color:#81908f;margin-top:5px}.note-meta{display:flex;flex-wrap:wrap;gap:8px;margin:15px 0 18px}.note-meta span{padding:5px 9px;border-radius:7px;background:#f4f6f8;color:#778295;font-size:8px;letter-spacing:.7px}.topic-video-card{display:grid;grid-template-columns:40px minmax(0,1fr) auto;align-items:center;gap:13px;margin:17px 0;padding:14px 16px;border:1px solid #e3e8ef;border-radius:13px;background:#fff;box-shadow:none}.video-icon{width:38px;height:38px;border-radius:11px;background:#fcebea;color:#c95a53}.topic-video-copy strong{font-size:12px;color:#2b374d}.topic-video-copy p{font-size:10px;line-height:1.55;color:#7b8698;margin:3px 0 0}.topic-video-link{font-size:10px;white-space:nowrap}.note-learning{margin:16px 0;padding:17px 19px;border:1px solid #e1e9f3;border-radius:13px;background:#f7f9fd;box-shadow:none}.note-learning h3{font-size:14px;color:#29364b}.note-learning ul{gap:8px 18px}.note-learning li{font-size:11px;line-height:1.65;color:#647187}
.visual-note-section{margin:10px 0;border:1px solid #e4e8ef;border-radius:13px;background:#fff;box-shadow:none;overflow:hidden}.visual-note-section:before{width:3px;background:#82bcb0}.interactive-section summary{padding:16px 17px}.note-section-number{width:30px;height:30px;border-radius:9px;background:#edf4f2;color:#32786f;font-size:10px}.section-summary-copy{gap:3px}.note-section-label{font-size:8px;letter-spacing:1px;color:#8893a4}.section-summary-copy strong{font-size:14px;color:#2c374c}.section-toggle{width:27px;height:27px;background:#f0f3f7;color:#617086;font-size:17px}.section-content{padding:0 18px 18px 61px}.concept-bites{gap:7px}.concept-bites li{grid-template-columns:24px minmax(0,1fr);gap:9px;padding:10px 12px;border:1px solid #edf0f4;border-radius:10px;background:#fafbfc;color:#58657a;font-size:11px;line-height:1.75}.bite-dot{width:23px;height:23px;background:#e5f3ef;color:#327a70;font-size:9px}.section-takeaway{gap:9px;margin-top:12px;padding-top:10px;border-top:1px solid #edf0f4}.section-takeaway span{font-size:8px;color:#2d8a7c}.section-takeaway strong{font-size:10px;color:#647187}.note-callout,.example-box{padding:17px 19px;border-radius:13px;box-shadow:none}.note-callout{background:#fff9ee;border-color:#f0e2c6}.example-box{background:#f0f8f5;border-color:#d8eae4}.note-callout>strong,.example-box>strong{font-size:9px;letter-spacing:1px}.note-callout p,.example-box p{font-size:12px;line-height:1.8;color:#566278}
.topic-test{margin-top:25px;padding-top:22px;border-top:1px solid #e7ebf1}.test-heading h3{font-size:20px;color:#27344a;margin:7px 0}.test-heading p{font-size:12px;color:#778297}.topic-test-question{padding:16px;margin:12px 0;border:1px solid #e3e8ef;border-radius:12px;background:#fff}.test-question-meta{display:flex;flex-wrap:wrap;justify-content:space-between;gap:8px;font-size:8px;color:#7c8799;letter-spacing:.7px}.topic-test-question h4{font-size:12px;line-height:1.7;color:#303d52;margin:10px 0}.written-answer,textarea,input,select{color:#29354b}.written-answer{width:100%;border:1px solid #dfe5ed;border-radius:10px;background:#fafbfd;padding:11px;font-size:12px}.written-answer:focus{border-color:#9bcbbf;box-shadow:0 0 0 3px #e3f3ee}.answer-hint{font-size:10px;color:#7b8698}.model-answer{padding:17px;border-radius:12px;background:#f4f8f6;border:1px solid #dceae5;color:#536278}.model-answer li{margin:7px 0;font-size:12px;line-height:1.8}.topic-test-actions{display:flex;flex-wrap:wrap;gap:9px}.note-footer{margin-top:23px;padding-top:15px;border-top:1px solid #e8ecf1;font-size:9px;color:#8a94a4}
.formula-grid{gap:14px}.formula-card{border:1px solid #e3e8ef;border-radius:14px;background:#fff;box-shadow:none}.formula-card:hover{border-color:#c5ded6;box-shadow:0 8px 22px #233c4d0b}.sequence-terms{gap:17px}.sequence-term{border:1px solid #e2e7ee;border-radius:15px;background:#fff;overflow:hidden;box-shadow:none}.sequence-term-head{background:#f5f8f7;border-bottom:1px solid #e6ebe9}.sequence-term-head h2{color:#2b374c}.sequence-table th{background:#fafbfc;color:#7b8697}.sequence-table td{color:#556177;border-color:#edf0f4}.sequence-note{border:1px solid #eadfca;background:#fff9ee;border-radius:12px;color:#665b48}.periodic-wrap{border:1px solid #e1e7ee;border-radius:15px;background:#fff;padding:14px;overflow:auto}.periodic-grid .element{border-radius:7px;border:1px solid #e4e9ef}.element-detail{border:1px solid #e1e7ee;border-radius:14px;background:#fff}.practice-layout,.tool-grid,.tutor-layout{gap:16px}.practice-main,.practice-side,.calculator-card,.tutor-chat,.tutor-guide,.privacy-note{border:1px solid #e3e7ee;border-radius:15px;background:#fff;box-shadow:none}.quiz-top{color:#718096}.quiz-progress-track{height:5px}.quiz-question h2,.quiz-question h3{color:#29364b}.quiz-option{border:1px solid #e2e7ee;border-radius:10px;background:#fff;color:#4e5c72}.quiz-option:hover{background:#f2f8f6;border-color:#bcdcd2}.quiz-option.selected,.quiz-option.correct{background:#e9f5f0;border-color:#9acbbb;color:#245f56}.quiz-option.incorrect{background:#fff1ef;border-color:#efc4bd;color:#9b4840}.result-box{border:1px solid #dce9e4;border-radius:10px;background:#f5faf8;color:#2f6259}.calculator-card label{color:#657187}.calculator-card input,.chat-compose textarea{border:1px solid #dfe5ed;border-radius:10px;background:#fafbfd}.tool-title h3{color:#29354b}.tutor-chat{overflow:hidden}.chat-header{border-bottom:1px solid #e8ecf1}.chat-messages{background:#fafbfd}.message.assistant .message-body{background:#fff;border:1px solid #e3e8ef;color:#4c5a70}.message-body strong{color:#2c384e}.suggestion-chips button{border:1px solid #dfe8e4;background:#f3f8f6;color:#35746b;border-radius:8px}.chat-compose{background:#fff;border-top:1px solid #e7ebf1}.send-button{background:#277e73;color:#fff;border-radius:10px}.chat-disclaimer{color:#8a94a4}.site-footer{border-top:1px solid #e2e7ee;color:#818b9b}.site-footer a{color:#287d70}
.toast{background:#202a40;color:#fff;box-shadow:0 8px 24px #202a4022}
@media(max-width:1150px){.feature-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.hero{gap:22px;padding:28px}.notes-layout{grid-template-columns:220px minmax(0,1fr)}}
@media(max-width:850px){.sidebar{width:245px;transform:translateX(-100%);transition:transform .22s ease}.sidebar.open{transform:translateX(0)}.main-area{margin-left:0}.content-wrap{padding:22px 18px}.topbar{padding:0 18px}.hero{grid-template-columns:1fr}.hero-visual{min-height:245px}.notes-layout{grid-template-columns:1fr}.topic-list{position:relative;top:auto;max-height:270px}.topic-hero{grid-template-columns:1fr}.topic-hero-art{display:none}.page-intro{align-items:flex-start}.lower-grid{grid-template-columns:1fr}}
@media(max-width:560px){.topbar{height:62px}.breadcrumbs{display:none}.top-actions{margin-left:auto}.global-search{max-width:175px}.content-wrap{padding:17px 12px}.hero{padding:23px 19px;min-height:0}.hero h1{font-size:37px;letter-spacing:-1.5px}.hero-visual{min-height:210px}.feature-grid{grid-template-columns:1fr 1fr;gap:9px}.feature-card{padding:14px}.feature-card p{font-size:10px}.card-bottom{font-size:9px}.page-intro{flex-direction:column}.intro-stat{display:flex;align-items:center;gap:10px;padding:10px 14px}.intro-stat strong{font-size:22px}.toolbar{flex-direction:column}.toolbar select{width:100%}.topic-video-card{grid-template-columns:36px minmax(0,1fr)}.topic-video-link{grid-column:2;justify-self:start}.note-learning ul{grid-template-columns:1fr}.section-content{padding:0 13px 14px}.interactive-section summary{padding:13px}.section-summary-copy strong{font-size:12px}.concept-bites li{font-size:10px;padding:9px}.topic-test-actions .btn{width:100%}.site-footer{flex-wrap:wrap;gap:9px}.site-footer>span:nth-child(2){width:100%;order:3}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;scroll-behavior:auto!important;transition:none!important}}
@media print{body{background:#fff}.sidebar,.topbar,.note-actions,.topic-video-card,.screen-only{display:none!important}.main-area{margin:0}.content-wrap{padding:0}.note-reader,.visual-note-section,.topic-test-question{box-shadow:none;break-inside:avoid}.interactive-section:not([open])>.section-content{display:block}.hero{box-shadow:none}}


/* VISUAL STUDY NOTES — cards, diagrams, short chunks, no text walls */
.visual-map-card{margin:18px 0 22px;background:linear-gradient(135deg,#f7fafc,#f0f7f5);border:1px solid #dce6e9;border-radius:18px;padding:19px 20px 15px;color:#243746;overflow:hidden}
.visual-map-heading{display:flex;align-items:center;gap:12px;flex-wrap:wrap;margin-bottom:8px}
.visual-map-heading span{font-size:9px;letter-spacing:1.5px;font-weight:800;color:#287c72;background:#dff1ec;padding:6px 9px;border-radius:7px}
.visual-map-heading strong{font:800 13px Manrope,sans-serif;letter-spacing:.2px}
.topic-diagram{display:block;width:100%;height:auto;max-height:190px;overflow:visible}
.visual-map-caption{font-size:11px;color:#647787;padding-top:7px;border-top:1px solid #dfe8eb}
.topic-key-chips{display:flex;gap:7px;flex-wrap:wrap;margin:15px 0 5px}
.topic-key-chip{font-size:11px;font-weight:700;color:#2a665f;background:#e3f2ed;border:1px solid #cde7df;border-radius:8px;padding:6px 9px}
.topic-hero-pills{display:flex;gap:7px;flex-wrap:wrap}
.topic-hero-pills span{font-size:9px;letter-spacing:.5px;font-weight:800;padding:6px 8px;border-radius:7px;background:#edf2f8;color:#52677a}
.note-learning{padding:18px!important}
.learning-route{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px;margin-top:14px}
.learning-route>div{display:grid;grid-template-columns:27px 1fr;column-gap:8px;align-items:center;padding:11px;background:#f4f7fa;border:1px solid #e2e9ee;border-radius:12px}
.learning-route>div>span{grid-row:span 2;display:grid;place-items:center;width:27px;height:27px;border-radius:9px;background:#dff1ec;color:#267a70;font-size:12px;font-weight:800}
.learning-route strong{font-size:10px;letter-spacing:.7px;color:#2b4054}
.learning-route small{font-size:10px;color:#758697;line-height:1.3}
.note-section-list{margin:20px 0}
.notes-list-heading{margin-bottom:12px}
.notes-list-heading h3{font:800 21px Manrope,sans-serif;margin:5px 0;color:var(--text)}
.notes-list-heading p{margin:0;color:var(--muted);font-size:12px}
.visual-note-section{border:1px solid var(--line);background:var(--panel);border-radius:14px;margin:9px 0;overflow:hidden}
.visual-note-section summary{list-style:none;display:flex;align-items:center;gap:12px;padding:15px;cursor:pointer}
.visual-note-section summary::-webkit-details-marker{display:none}
.visual-note-section summary:hover{background:#f1f6f7}
.visual-note-section .note-section-number{display:grid;place-items:center;flex:0 0 36px;height:36px;border-radius:11px;background:#e4f2ee;color:#287c72;font:800 12px Manrope}
.section-summary-copy{display:grid;gap:3px;flex:1;min-width:0}
.visual-note-section .note-section-label{font-size:8px;letter-spacing:1.3px;font-weight:800;color:#6b8a93}
.visual-note-section summary strong{font:750 14px Manrope,sans-serif;color:#243746}
.section-toggle{display:grid;place-items:center;width:26px;height:26px;border-radius:50%;background:#edf2f5;color:#3d6d71;font-size:18px;transition:transform .18s}
.visual-note-section[open] .section-toggle{transform:rotate(45deg)}
.visual-note-section .section-content{padding:0 15px 15px 63px}
.concept-bites{display:grid;gap:8px;margin:0;padding:0}
.concept-bite{display:grid;grid-template-columns:25px minmax(0,1fr);gap:9px;align-items:start;padding:10px 11px;background:#f6f8fa;border:1px solid #e8edf0;border-radius:10px;color:#354a5d;font-size:12px;line-height:1.55}
.bite-dot{display:grid;place-items:center;width:23px;height:23px;background:#e0eeeb;color:#287c72;border-radius:7px;font-size:9px;font-weight:800}
.section-takeaway{display:flex;align-items:center;gap:9px;flex-wrap:wrap;margin-top:11px;padding:9px 11px;border-left:3px solid #66b3a4;background:#eaf5f1;border-radius:0 8px 8px 0}
.section-takeaway span{font-size:8px;letter-spacing:1.2px;font-weight:800;color:#287c72}
.section-takeaway strong{font-size:11px;color:#315b59}
.visual-callout{display:flex;align-items:flex-start;gap:12px;margin:15px 0;padding:16px;border:1px solid #ead8ae;border-radius:14px;background:#fff8e9;color:#574728}
.callout-icon{display:grid;place-items:center;flex:0 0 30px;height:30px;border-radius:9px;background:#f3e0b5;font-weight:900;color:#875c16}
.visual-callout>div:last-child{min-width:0}
.visual-callout strong{font-size:10px;letter-spacing:1.1px}
.callout-bites{display:grid;gap:7px;margin-top:8px}
.callout-bite{font-size:12px;line-height:1.5;padding:8px 10px;background:#fffdf8;border-radius:8px}
.visual-example{padding:16px;border:1px solid #dce6f0;border-radius:14px;background:#f1f6fc;color:#2b4156}
.example-heading{display:flex;align-items:center;gap:10px;margin-bottom:12px}
.example-heading>span{display:grid;place-items:center;width:32px;height:32px;border-radius:10px;background:#dce8fb;color:#476cb7;font-size:18px}
.example-heading>div{display:grid;gap:2px}
.example-heading strong{font-size:10px;letter-spacing:.9px}
.example-heading small{font-size:10px;color:#73869b}
.example-bites{display:grid;gap:8px}
.example-bite{display:grid;grid-template-columns:24px 1fr;gap:9px;align-items:start;padding:10px;background:#fff;border:1px solid #e1e9f1;border-radius:10px;font-size:12px;line-height:1.55}
.example-bite>span{display:grid;place-items:center;width:23px;height:23px;border-radius:7px;background:#e4edfc;color:#466bb5;font-weight:800;font-size:10px}
.revision-card-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:12px}
.revision-card-grid article{padding:12px;background:#f7f9fb;border:1px solid #e2e9ee;border-radius:12px;color:#31475b;font-size:11px}
.revision-card-grid article>span{display:block;color:#32877b;font-size:9px;font-weight:800;letter-spacing:1px;margin-bottom:5px}
.revision-card-grid article>strong{display:block;font-size:12px;margin-bottom:9px}
.revision-card-grid .concept-bite{font-size:10px;padding:7px;background:#fff}
.topic-test-question{border-radius:13px}
@media(max-width:720px){.visual-map-card{padding:14px 12px}.visual-map-heading strong{font-size:11px}.topic-diagram{max-height:150px}.learning-route{grid-template-columns:1fr}.learning-route>div{grid-template-columns:27px 1fr}.visual-note-section .section-content{padding:0 10px 12px}.visual-note-section summary{padding:11px;gap:8px}.revision-card-grid{grid-template-columns:1fr}.concept-bite{font-size:11px}}
@media print{.visual-map-card,.visual-callout,.visual-example,.visual-note-section,.revision-card-grid article{break-inside:avoid}.visual-note-section:not([open]) .section-content{display:block}.topic-video-card,.topic-test-actions,.screen-only{display:none!important}}

.illustration-gallery{margin:18px 0 23px}
.gallery-heading{display:flex;align-items:end;justify-content:space-between;gap:10px;margin-bottom:11px}
.gallery-heading h3{font:800 19px Manrope,sans-serif;color:var(--text);margin:3px 0 0}
.gallery-count{font-size:9px;letter-spacing:1px;font-weight:800;color:#6c8191}
.illustration-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}
.illustration-card{min-width:0;overflow:hidden;background:#fff;border:1px solid #e0e8ed;border-radius:15px;padding:10px;color:#30475a;box-shadow:0 4px 16px #102b3a08}
.illustration-art{display:grid;place-items:center;min-height:94px;background:linear-gradient(145deg,#f4f8fc,#eaf5f2);border-radius:10px;margin-bottom:10px}
.illustration-art svg{display:block;width:100%;max-width:150px;height:94px}
.illustration-label{display:block;color:#398579;font-size:8px;letter-spacing:1.2px;font-weight:800;margin-bottom:5px}
.illustration-card strong{display:block;font:750 12px Manrope,sans-serif;line-height:1.4;min-height:33px}
.illustration-caption{display:block;margin-top:5px;color:#8493a0;font-size:10px}
@media(max-width:720px){.illustration-grid{grid-template-columns:1fr}.illustration-card{display:grid;grid-template-columns:94px minmax(0,1fr);grid-template-rows:auto auto 1fr;column-gap:12px;align-items:start}.illustration-art{grid-row:1/4;min-height:90px;margin:0}.illustration-art svg{height:90px}.illustration-label{padding-top:3px}.illustration-card strong{min-height:0}.illustration-caption{margin-top:3px}}


/* NEW VISUAL IDENTITY: midnight plum, warm paper, coral and jade */
:root{
 --bg:#f6f3ef;
 --panel:#fffdfa;
 --panel-2:#f0ebe5;
 --text:#292638;
 --muted:#777180;
 --line:#e5ddd5;
 --primary:#b64f58;
 --primary-hover:#963e48;
 --accent:#347b70;
 --sidebar:#242237;
 --sidebar-text:#f5f0f7;
 --shadow:0 12px 34px rgba(42,30,47,.07);
}
body,.app-shell,.main-content{background:#f6f3ef!important;color:#292638}
.sidebar,.app-sidebar,.side-nav{background:#242237!important;color:#f5f0f7!important}
.sidebar .nav-link,.app-sidebar .nav-link,.side-nav a{color:#d6d0e0}
.sidebar .nav-link.active,.app-sidebar .nav-link.active,.side-nav .active{background:#3a354f!important;color:#fff!important;border-left-color:#e47d7c!important}
button.btn-primary,.btn-primary{background:#b64f58!important;border-color:#b64f58!important;color:#fff!important}
button.btn-primary:hover,.btn-primary:hover{background:#963e48!important}
.btn-secondary{background:#fffdfa!important;color:#423b50!important;border-color:#e5ddd5!important}
a{color:#347b70}
.card,.topic-card,.feature-card,.formula-card,.quiz-card,.note-section,.visual-note-section{background:#fffdfa;border-color:#e5ddd5}
.topic-hero{background:linear-gradient(120deg,#f4e9e3 0%,#f5f0e9 52%,#e5efeb 100%)!important;border-color:#e7d9d0!important}
.topic-hero-label,.section-kicker,.note-section-label{color:#a24b56!important}
.topic-hero-pills span{background:#e9e3ed;color:#50465f}
.topic-key-chip{background:#e3efea;border-color:#d0e4dc;color:#2e6d63}
.visual-map-card{background:#fffdfa;border-color:#e5ddd5}
.visual-map-heading span{background:#f4e2e0;color:#a34750}
.visual-map-caption{color:#777180;border-color:#e5ddd5}
.illustration-grid{grid-template-columns:repeat(3,minmax(0,1fr))}
.illustration-card{padding:10px;background:#fffdfa;border-color:#e5ddd5;box-shadow:0 8px 22px rgba(42,30,47,.05)}
.illustration-card .photo-link{display:block;overflow:hidden;border-radius:10px;margin-bottom:10px;background:#eee7e1}
.illustration-card .photo-link img{display:block;width:100%;height:145px;object-fit:cover;transition:transform .35s ease}
.illustration-card .photo-link:hover img{transform:scale(1.04)}
.illustration-label{color:#a24b56}
.illustration-card strong{color:#292638}
.illustration-caption,.gallery-count{color:#777180}
.image-credit{font-size:10px;line-height:1.5;color:#8b8490;margin:9px 0 0}
.image-credit a{color:#347b70;text-decoration:underline;text-underline-offset:2px}
.topic-photo-wrap{position:relative;overflow:hidden;border-radius:15px;background:#e8e0dc}
.topic-photo{display:block;width:100%;height:185px;object-fit:cover;border-radius:15px}
.topic-photo-caption{position:absolute;left:10px;bottom:10px;padding:6px 8px;border-radius:6px;background:rgba(36,34,55,.84);color:#fff;font-size:8px;font-weight:800;letter-spacing:1px}
.topic-wide-photo{display:block;width:100%;height:240px;object-fit:cover;border-radius:12px}
.visual-note-section summary:hover{background:#f6f0ed}
.visual-note-section .note-section-number{background:#f4e2e0;color:#a34750}
.section-toggle{background:#f0ebe5;color:#347b70}
.section-takeaway{border-left-color:#347b70;background:#e8f1ed}
.section-takeaway span{color:#347b70}
.concept-bite{background:#f8f4f0;border-color:#ece3dc;color:#3e3948}
.bite-dot{background:#f4e2e0;color:#a34750}
.visual-callout{background:#fff4df;border-color:#eddcb9;color:#5e4b2d}
.example-bite{border-color:#e5ddd5}
.example-bite>span{background:#f4e2e0;color:#a34750}
.learning-route>div>span{background:#e3efea;color:#347b70}
@media(max-width:720px){.illustration-grid{grid-template-columns:1fr}.illustration-card .photo-link img{height:185px}.topic-wide-photo{height:180px}}
@media(prefers-reduced-motion:reduce){.illustration-card .photo-link img{transition:none}}